Can my daughter stop laser treatement for PWS after 10 treatments?

[zhou]

My daughter had 10 times v-beam 595 treatment already on cheek for PWS. She is 8 years old now. It helped and we are satisfied although it did not fully disappear.
Now we just want to maintain the effect.
Can we stop laser treatment or we need to keep on like once a year to maintain the effect?
I heard before once you used laser you have to keep on the life time, otherwise it will resurge. Is that true?
Looking forward to advice.